{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T14:27:11Z","timestamp":1790519231410,"version":"4.1.0"},"reference-count":47,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,24]],"date-time":"2020-12-24T00:00:00Z","timestamp":1608768000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004508","name":"Prince of Songkla University","doi-asserted-by":"publisher","award":["SCI6201170s"],"award-info":[{"award-number":["SCI6201170s"]}],"id":[{"id":"10.13039\/501100004508","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Higher Education Research Promotion and the Thailand\u2019s Education Hub for Southern Region of ASEAN Countries Project Office of the Higher Education Commission","award":["Bashir Algaily"],"award-info":[{"award-number":["Bashir Algaily"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The property retentions of silica-reinforced natural rubber vulcanizates with various contents of a self-healing modifier called EMZ, which is based on epoxidized natural rubber (ENR) modified with hydrolyzed maleic anhydride (HMA) as an ester crosslinking agent plus zinc acetate dihydrate (ZAD) as a transesterification catalyst, were investigated. To validate its self-healing efficiency, the molecular-scale damages were introduced to vulcanizates using a tensile stress\u2013strain cyclic test following the Mullins effect concept. The processing characteristics, reinforcing indicators, and physicomechanical and viscoelastic properties of the compounds were evaluated to identify the influences of plausible interactions in the system. Overall results demonstrate that the property retentions are significantly enhanced with increasing EMZ content at elevated treatment temperatures, because the EMZ modifier potentially contributes to reversible linkages leading to the intermolecular reparation of rubber network. Furthermore, a thermally annealing treatment of the damaged vulcanizates at a high temperature, e.g., 120 \u00b0C, substantially enhances the property recovery degree, most likely due to an impact of the transesterification reaction of the ester crosslinks adjacent to the molecular damages. This reaction can enable bond interchanges of the ester crosslinks, resulting in the feasibly exchanged positions of the ester crosslinks between the broken rubber molecules and, thus, achievable self-reparation of the damages.<\/jats:p>","DOI":"10.3390\/polym13010039","type":"journal-article","created":{"date-parts":[[2020,12,24]],"date-time":"2020-12-24T09:02:44Z","timestamp":1608800564000},"page":"39","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Alleviating Molecular-Scale Damages in Silica-Reinforced Natural Rubber Compounds by a Self-Healing Modifier"],"prefix":"10.3390","volume":"13","author":[{"given":"Bashir","family":"Algaily","sequence":"first","affiliation":[{"name":"Polymer Science and Technology, Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai Campus, Songkhla 90110, Thailand"},{"name":"Department of Physics, Faculty of Science and Technology, Al-Neelain University, Khartoum 11111, Sudan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8369-4575","authenticated-orcid":false,"given":"Wisut","family":"Kaewsakul","sequence":"additional","affiliation":[{"name":"Elastomer Technology and Engineering, Department of Mechanics of Solids, Surfaces and Systems, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7522 NB Enschede, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siti Salina","family":"Sarkawi","sequence":"additional","affiliation":[{"name":"Malaysian Rubber Board, RRIM Research Station, Sg. Buloh, Selangor 47000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1277-1123","authenticated-orcid":false,"given":"Ekwipoo","family":"Kalkornsurapranee","sequence":"additional","affiliation":[{"name":"Polymer Science and Technology, Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai Campus, Songkhla 90110, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"536","DOI":"10.1016\/j.pmatsci.2016.07.007","article-title":"Cracks, microcracks and fracture in polymer structures: Formation, detection, autonomic repair","volume":"83","author":"Awaja","year":"2016","journal-title":"Prog. Mater. 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